Ventilator



Nov. 17, 1936. c. DAVIES Q 2,061,535

VENTILATOR Filed April 15, 1932 INVENTOR C/ggrles Dal/[a5 ATTORN Y Patented Nov. 17, 1936 UNITED STATES PATENT OFFICE 12 Claims.

This invention relates to ventilators of the type adapted to be mounted in the window of a room; and including provisions for producing a flow of pure filtered air adequate to the purpose intended. Such a ventilator comprises generically a case containing an air filter, a motor-driven air impeller to produce a current of air through the filter, and the various ducts necessary to direct the flow of air. The operation of such a ventilator, as heretofore constructed, is accompanied by a considerable amount of hum and other noise; which, as may be readily understood, constitutes a serious objection for many people and for many purposes against this type of ventilator.

The main object of my invention, therefore, is to provide a ventilator of this general type, capable of providing a sufiicient volume of pure, filtered air and yet substantially noiseless. While the exact manner in which the noises arise is still rather obscure, experience has shown that such noises are developed and transmitted both directly and mediately in the air currents produced by the air pump or blower and the reactions of the said currents with the walls of the impeller casing and the ducts associated therewith. I have discovered that such noises are almost completely suppressed by embedding, forming or cutting the impeller scroll or casing and the exit air ducts in a body of sound absorbing material of substantial thickness. The main feature of my invention, therefore, consists in forming the scroll of the air impeller and the associated delivery duct as a continuous passageway in a block of sound absorbing material.

Another important feature of my invention is a simple and efficient method of mounting and interrelating the rotor or impeller of the air pump and the sound absorbing block so as to provide for a quick and accurate assembly of the air impeller in relation to the scroll and duct.

A further feature of my invention is the provision of a separate air ingress chamber wherein the filter is mounted to permit quick and ready access for removal and replacement without disturbing the air pump assembly. At the same time the assembly of the entire ventilator is simplified and facilitated.

These and other and further objects, features, and advantages of my invention will appear in more detail in the description hereinafter, in

' connection with the drawing, of a preferred embodiment of my invention.

In the drawing:

Fig. 1 is a plan view of my ventilator, the cover being removed.

Fig. 2 is a rear elevation of my ventilator.

Figs. 3 and 4 are sectional views taken along the lines 3-3 and 44 respectively of Fig, 2 looking in the direction of the arrows.

My ventilator comprises a rectangular case which may conveniently be made of wood or metal; and is provided with an imperforate bottom I and a removable cover 2 at the top. The front Wall 3 is provided at the bottom with an air intake opening 4, which as shown may be protected by louvres. The rear wall 5 is provided at its upper portion with an air exit opening 6, also protected by louvres. Interiorly the case is divided into two compartments or chambers by the horizontal partition and mounting plate 'I which may conveniently be supported on and secured to flanges 8 on the interior of the case.

The lower compartment 9, communicating with the air intake opening 4, comprises the air intake chamber and contains the air filter which may be mounted across it. The air filter comprises an open, double frame II], hinged at one end as at I I, and resting in an inclined position on ledges I2, I3 on the front and rear walls of the case and on side ledges (not shown). The ledge I2 is positioned on the wall 3 above the opening 4 and supports the hinged end of the frame. The ledge I3 is located on the wall 5 near the bottom and supports the separable end of the frame. A corrugated filter insert having a fiat edge adapted to be held between the frame members is positioned in the frame. The filter insert I4 is similar in construction to the one shown in my co-pending application for Filters, Ser. No. 577,177 filed Nov. 25, 1931, now Patent No. 1,890,499, patented Dec. 13, 1932. A door I5 permits access to frame I0; and, when closed, abuts the end of the frame and aids in holding it in position. A flange I6 on the inside of the door presses against the upper member of frame I0 and in co-operation with ledge I3 holds the frame securely closed.

The mounting plate "I has an upward, hollow, frusto-conical projection I! which provides a passageway leading out of the filter chamber 9. An electric motor I8 is mounted in the passageway by means of the webs I9 secured to the inner wall of the projection I I. The motor carries on its shaft and operates the rotor or impeller 29 of a centrifugal air pump, the rotor being located just above the free edge of the duct I7 and in position to receive its air supply from the latter. The upper compartment of the case is occupied by the block 2| which fits over and around the impeller 20 and the conical duct IT. The block 2I is made of sound absorbing material, numerous varieties of which are now available. The block is formed with a hollow shaped to co-operate with the rotor 20 and provide therefor an air collecting scroll and a delivery duct 23. The block 2| rests upon or is secured to the fiat part of the plate I, the scroll portion 22 at its lower end surrounding the air supply duct l1, and at its upper end surrounding the impeller 2|]. The duct 23 followsia twisted or recurved. path from the outlet of the scroll 22 to the ultimate air outlet 6. The scroll portion 22 and the duct 23 have been shown in the drawing as extending from top to bottom of the blockrbut it is clear that this is a matter of-convenience in construction only. The passageway 22, 23 may be enclosed above and beiowdn'an obvious manner. The block itself and the passageway 22, 23 may be constructed by pouring or molding appropriate material with good results; I have, however, found it simpler and more convenient to build the block of lamina 24* which may be cut in advance and piled flat one upon the other. I The pile may then be securely tied together by one or more bolts 25. If de sired one or more imperforate lamina may be added at the top of the pile; and the lower laminae may be continuous except 'for theperforation necessary to accommodate the duct l1. 1 I have, however, found the simpler construction shown in the drawing sufiicient for most purposes. The laminae themselves are of a cellular, woodlike "composition material having good sound absorbing characteristics; but oil course my invention is not limited to the'specific material, the sole requirement being that the material have good sound absorbing or insulating quali- 'The block 2|, as a whole, fits over and around the rotor 20 of mean pump and is mounted substantially independently'of the-same. "It may be said that the air pump comprises the rotor 20 and the statorparts i1 and 22, the intake ductll'being formed-as a part of the plate I. and the collecting scroll 23 as part of the block 2|. It will be noted that themass of sound absorbing material 2|- rests" upon the plate 1 and'surrounds'the'duct i1 and acts to damp out and prevent the transmission of sound from vibrations'developed in plate'l and 'duct I! by imperfections in the .:rotating' 'parts. Noises due to and carried bythe air'currents themselves are "efiectually absorbed and suppressed by the walls of the scroll 22 and the long duct 23.

The operation of my ventilator is apparent from the foregoing description. Under the action of the pump impeller"2|| air iromthe exterior enters chamber 9 through opening 4, passes through filter I4 into'duct I'I. Thence it is delivered, by way of collecting scroll 22, to the delivery duct 23 which delivers it "to the room to be ventilated by way'of the opening 6. The noises incidental to the operation of the pump are absorbed and suppressedby the .walls of the scroll 22 and duct 23 and the mass of the block 2|; The filter islocated in'a separate chamber 9 and may be removed and replaced without disturbing the rest, of the structure. Todo so, the door I5 is opened orremoved and the frame I0 withdrawn thruthe opening. The filterinsert may then be taken out of the frame and a fresh one inserted. "Of course it is not necessary to remove theframe itself; and, if desired, the latter may be fixedly secured to the ledges l2 and 3, only the upper member of the frame being movable.

In compliance with the statute, I have described hereinabove a preferred embodiment of my invention; but it is to be understood that 5 numerous modifications in detail may be made therein without departing from the spirit and scope of my invention. What I claim as my invention is:

1. In a ventilator, a plate formed with a pro- 10 jecting air duct, an air impeller mounted to the wall of said duct in position to draw air therefrom, a block fitting over the impeller and supported by the plate and provided with a channel constituting a collecting scroll and de- 15 livery duct for the impeller.

- 2. "In a ventilator, a plate formed with a projecting air duct, an air impeller mounted to the wall of said duct in position to draw air therefrom,a blockof sound absorbing material supported on theplate and fitting over the impeller and provided with a channel constituting a collecting scroll and delivery duct for the impeller. I

3. In'a'ventilator, a plate formed with a projecting air duct, an air impeller mounted to the wall of said duct in position to draw air therefrom, a block fitting overthe impeller and supported by the plate, said block comprising a series oi'superposed laminae cut to provide in cooperationa channel constituting a scroll and delivery duct for the impeller.

4. In a ventilator, a plate formed with a projecting air duct, an air impeller mounted to the wall of said duct in position to draw airtherefrom; a block fitting over the impeller and supported by the plate, said block comprising a series of superposed laminae of sound absorbing material-cut to provide in co-operation a chan-- nel constituting a collecting scroll and air delivery duct for the impeller. v

5. In'aventilator a case having an air intake chamber,--an air filter across the intake chamber, aplate constituting one wall of the intake chamher and formed with a duct leading from the said 45 chamber an air impeller mounted at the outlet of the said duct, a block supported by the plate and fitting over the impeller and providing in its body an air collecting scroll and delivery tube for the impeller." 50

6. In aventilator, a case having an air intake-chamber, an air 'filter across the intake chamber, a plate constituting one wall of the intake chamber and formed with a duct leading from thesaid chamber, an air impellermounted 55 at the outlet of the said duct, a block oi sound absorbing material supported by the plate and fitting over the impeller and providing in its body an air collecting scroll and delivery duct for the impeller. 7. In a ventilator, a case havingan air intake chamber, an air filter across the intake chamber, a plate constituting one wall of the intake chamber'and formed with a duct leading from the said chamber, an air impeller mounted at the outlet of the said duct, a block supported bytheplate and fitting over the impeller, said block comprising a series of superposed laminae cut to provide in co-operation a channel constituting an W air collecting scroll and delivery duct for the impeller. a i i 8. In a ventilator, a case having an air intake chamber, an air filter across the intake chamber,

a plate constituting one wall of the intake chamher and formed with a duct leading from the said 7 chamber, an air impeller mounted at the outlet of the said duct, a block supported by the plate and fitting over the impeller, said block comprising a series of superposed laminae of sound absorbing material cut to provide in co-operation a channel constituting an air collecting scroll and a delivery duct for the impeller.

9. In a ventilator, a case provided with an air intake chamber, a filter across the said chamber, said filter comprising an open, jointed frame holding a filter body, and a door in one wall of the case permitting inspection and replacement of the filter body, and means on the door to hold together the members of the frame when the said door is closed.

10. In a ventilator, a case provided with an air intake chamber, an air filter mounted across the said chamber, said filter comprising a jointed, open frame holding a filter insert, a door in one wall of the case having provisions to hold together the members of the frame when the said door is closed, a plate constituting another wall of the said chamber and formed with a duct leading from said chamber, and an air impeller mounted at the outlet of said duct.

11. A ventilator comprising a case, a partition across the case dividing the latter into a filtering chamber and a pump chamber, said partition being provided with means communicating the two chambers, an air filter across the filtering chamber, an impeller in the pump chamber to pass air through the aforementioned communicating means, and a block supported by the partition and fitting over the said impeller and formed with passageways co-operating with the said impeller and constituting a duct for the passage of air moved by the impeller.

12. A ventilator comprising a case, a partition across the case dividing the latter into a filter chamber and a pump chamber, said partition being provided with means communicating the two chambers, an air filter across the filter chamber, an impeller mounted in the pump chamber to pass air through the aforesaid means, and a block of sound absorbing material supported by the partition and fitting over the said impeller, the said block being formed with a channel surrounding the impeller and leading away therefrom, the said channel providing a duct through which air is moved by the impeller.

CHAS. DAVIES 

